Despite the leaks, Sony still managed to keep some of the info on the portable under wraps. As part of its press conference today, Sony announced that the PSP Go will debut alongside Polyphony Digital's Gran Turismo PSP on October 1. The handheld will cost $249.99/€249.99, the same price as the original PSP when it went on sale in 2005.

First teased way back in 2004, Gran Turismo PSP is what Polyphony Digital founder Kazunouri Yamauchi called "a full-sized Gran Turismo," running at a 60 frames per second. The portable title has 800 cars packed into it, as well as 35 tracks with 60 different layouts associated with them. Single-player options for Gran Turismo PSP include a time-trial mode and a training mode. The game will also support multiplayer for up to four, and players will also be able to share and trade cards with others.

That wasn't the only PSP-related news, however. Kojima Productions head Hideo Kojima also took the stage with news of Metal Gear Solid: Peace Walker, word of which leaked out yesterday. Whether the primary protagonist is Solid Snake or Big Boss is yet to be determined. The game will be set in the 1970s, some 10 years after Metal Gear Solid 3. "It's a true sequel to the MGS franchise," Kojima noted.

Kojima offered press conference attendees a trailer for Peace Walker, showing footage of a 1950s-era nuclear bomb test as a voice-over warns against the Cold War arms race. Peace Walker will be set in Latin America, with shots from the trailer showing Snake delving into jungle environments. Then, a shot shows a full squad of Solid Snake/Big Boss characters, battling against what appeared to be an airborne Metal Gear.

Metal Gear Solid: Peace Walker is expected to arrive for the PSP in 2010.